1. Field of the Invention
This invention relates to a method of constructing tanker ships for transporting low temperature liquefied gases such as petroleum gases which are in a gaseous state at room temperature and can be liquefied under atmospheric pressure. More particularly, this invention relates to a method of constructing low temperature liquefied gas tanker ships equipped with containers made of low temperature resisting material, said containers each being positioned in a hold space defined by the inner wall of a hull and a bulkhead with interposition of a heat insulating layer.
2. Description of the Prior Art
As a conventional method of constructing the low temperature liquefied gas tanker ships of the above-mentioned structure, it has been proposed for the purpose of shortening the period of occupying a dock to construct tank assemblies each being made of said container and said heat insulating layer, the latter being provided over the outer surface of the former, separately from and in parallel with the hull of the tanker ship which is formed with the hold spaces for receiving said tank assemblies, and thereafter, to mount the tank assemblies into the hold spaces by suspending the tank assemblies by a crane or cranes and lowering them into the hold spaces of the hull. However, this method of construction involves a problem that it requires a heavy crane by which very large suspension height as well as reach are available.